[ANDROIDHASSAN]

Problem: safe_render (used by Instructions.render and Instructions.resolve_template) converts nested dicts to SimpleNamespace so templates can use dotted access like {user.name}. That conversion drops item access: SimpleNamespace has no __getitem__, so the standard str.format lookup {user[name]} raises TypeError. The error is caught, logged as a missing placeholder, and the field renders empty, even though the key is present in data:

Instructions("Hello {user[name]}").render(data={"user": {"name": "Alex"}})
# main: 'Hello '   (and logs "template placeholder '{user[name]}' has no value")

This also breaks keys that are not valid identifiers, which only [key] can reach, such as {user[support-tier]}.

Fix: convert nested dicts to a small SimpleNamespace subclass that also implements __getitem__ from its __dict__. Dotted access is unchanged and [key] works again, as with a plain str.format on the dict. The subclass keeps the namespace type name, so a whole-dict placeholder such as {user.account} still renders namespace(plan='pro'). A missing key still raises KeyError, so it still renders empty and logs through the existing handler in _Fmt.get_field.

Tests

Six nested-dict-* cases added to the parametrized test_render in tests/test_instructions.py (moved there from test_chat_ctx.py after #8510 folded the instructions tests into that module). {user[name]}, {user[account][plan]}, {user.account[plan]} and {user[support-tier]} each fail on main with an empty render. {user.name} and {user.account} pass on main and stay as guards for dotted access and for the rendered namespace(...) repr.

$ uv run pytest tests/test_instructions.py -k nested -q   # utils/misc.py from main
4 failed, 2 passed, 50 deselected
$ uv run pytest --unit --audio_eot -q   # after merging main
6236 passed, 4 skipped

ruff format, ruff check and make type-check are clean.

Scope: only safe_render in utils/misc.py and its test cases. Missing-placeholder handling, None rendering and the logged list of available paths are unchanged. Lists inside data are not converted, so {items[0][name]} behaves as before.

[chatgpt-codex-connector]

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Review	Status	Commit	Review trigger
📝 Code Review	⚠️ Failed 2026-10-26T19:26:05.526822Z We couldn’t complete this review. Comment @codex review to try again.	8701920	PR opened

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[RaphaelFakhri]

I checked out 83d5ed9 and ran the change against main with a set of edge-case templates outside the new test. Results match plain str.format on the dict in every case I tried:

• {user[a.b]} (key with a dot) renders dot, {user[name][0]} renders A, and {user[name]:>6} and {user[name]!r} keep the spec and conversion. All of these render empty on main.
• {items[0][name]} on a list of dicts and {nested_list[xs][0][q]} resolve, since lists stay unconverted.
• {user[missing]}, {user[account][missing]}, {user[__dict__]} and {user[__class__]} render empty and log through the existing handler. Item lookup reads only __dict__, so it adds no attribute access beyond what dotted lookup already allows.
• {user[0]} with a string key "0" renders empty, same as str.format, which turns a digit-only index into an int.
• {user}, {user!r} and nested values render namespace(...) on Python 3.10, 3.11, 3.12, 3.13 and 3.14, so the __name__ override holds across the supported range.

tests/test_chat_ctx.py passes (93 passed, 1 skipped), and the new test fails 4 of 6 cases with utils/misc.py reverted.

One optional follow-up: the safe_render docstring still describes only dotted access. Since keys such as support-tier are now reachable only through [key], you could mention that form there too.